I installed two switches ; UP switch and Down switch ; as shown on the diagram attached, I configured both switches with VRRP between the two switches , these switches are connected to two core switches ; core 1 and core 2; core 2 should be the backup of core 1.
Both UP and Down switches are connected to a rack with many servers inside, these servers have IP's in networks 10.2.17.0 , and the gateway of servers is 10.2.17.1 which is configured on UP switch for vlan 1.
When someone try to connect ping to server on the rack some servers loose connection and the extended ping oscillates between reply and request timed out.
I attached the diagram and configuration of both switches, I need also to know if VRRP is configured correctly because it is the first time I'm doing it in production network?

Sorry I forgot the redundant link between the core switches, I modified the diagram and attached it.
I need to add that when I try to ping from down switch to networks 10.2.17.0, 10.2.18.0 and 10.2.20.0 I cannot ping.

The VRRP between the two down and UP switches are required because they will handle a critical system, and all servers will be connected to both switches, I'm responsible of these switches , I cannot access the core switches.
I need to know if this design can be implemented to work fine or not.

Yes. You're collapsed differently. Your design is not collapsing core+distribution (my assumption, sorry...didn't realise that you can't control the cores). Your design is collapsing access+distribution. This collapsed layer is your boundary between L2 & L3. This boundary is the place to have VRRP/HSRP.

Your addressing is a little confusing.
Your SwDN doesn't have an IPv4 address for vlan 1. SwUP is holding the .1 address. The virtual IP is .3
My numbering would be something like this:

Any misconfiguration or routing problem, and traffic will go to default route (0.0.0.0) which would be expected to jump to your core and out to the internet.

I fight that problem all the time...somebody "designed" with IP addresses that are _not_ private, non-routable IP addresses. Anything that isn't handled explicitly by a created route will jump to the nearest internet connection.

"Kindly, How to configure 10.2.17.1 on the switches to be the default gateway connected to them?
Thanks,"

--If you would like for the IP above to be a DG for your servers....then i would not use the management VLAN1 and create a new SVI (e.g. VLAN 10) with the interface IP of 10.2.17.1 and then place servers in that vlan.

This LINK may help you. with quoted text above. Let me know what you need for the other stuff.

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